Year	Number of
1990	384.97
1991	400.54
1992	415.4
1993	428.64
1994	463.88
1995	471.68
1996	467.35
1997	447.43
1998	457.12
1999	470.54
2000	474.72
2001	475.11
2002	473.44
2003	479.84
2004	486.79
2005	481.83
2006	498.43
2007	513.02
2008	526.15
2009	537.63
2010	551.35
2011	544.89
2012	547.72
2013	553.32
2014	571.69
2015	564.48
2016	556.53